V-type engine



June 8, 1954 R. F. suMMERs 2,680,427

V-TYPE ENGINE Filed Jan. 3l, 1952 3 Sheets-Shee':I 1

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Array/W506i June 8, 1954 R.' F. sUMMERs 2,680,427

V-TYPE ENGINE Filed Jan. 31, 1952 3 Sheets-Sheet 2 ffl, :55, .55,5212Slg-152x574 INVENTOR. derf Sarrrmfs'. BY

June 8, 1954 R; F. suMMERs 2,680,427

V-TYPE ENGINE Filed Jan. 3l, 1952 3 Sheets-Sheet 3 l l l HWWQHW PatentedJune 8, p 1954 UNITED STATES PATENT OFFICE V-TYPE ENGINE Robert F.Summers, Highland Park, Mich., as-

signor to Chrysler Corporation, Highland Park, Mich., a corporation ofDelaware Application January 31, 1952, Serial No. 269,227

26 Claims. 1

rIhis invention relates to odd angle V-eight internal combustion enginesand particularly to the bank angle and crankshaft crank arrangements forsuch engines whereby a completely balanced engine may be achievedwithout the use of socalled accessory counterbalance equipment.

It is a primary object of this invention to determine what cylinder bankanglesl other than the conventional 90 and 180 degree bank angle can beused in V-eight engines to provide an even firing, equal Cylinder borespaced engine that can be completely balanced by crankshaftcounterweighting alone. l

It is another object of this invention to determine the crankshaft crankarrangement for odd angle, even firing V-eight engines that will permitcomplete balance of the engine by the utilization of crankshaftcounterweighting alone.

Other objects and advantages of this invention will become readilyapparent from a reading of the following description and a considerationof the related drawings wherein:

Fig. 1 is a diagrammatic perspective view of a crankshaft for one of thebalanced, odd angle, V-eight engines embodying this invention, certainof the cranks of the crankshaft having the pistons, connecting rods andcounterweights connected thereto also shown in diagrammatic form;

Fig. 2 is a diagrammatic end elevation of the crankshaft and associatedengine structure shown in Fig. l, the View being taken in the directionof the arrow 2 of Fig. l;

Fig. 3 is another diagrammatic end elevation of the structure shown inFig. 1 illustrating the 6 wherein the crankshaft cranks are arranged ina pattern opposite to that shown in Fig. 7;

Fig. 9 is a diagrammatic end elevation of another form of odd angle,balanced V-eight engine embodying this invention;

Fig. 10 is a diagrammatic end elevation showing the crankshaft crankpinand the connecting rod arrangement for the engine shown in Fig. 9;

Fig. 11 is a diagrammatic end elevation showing the crankshaft crankpinand the connecting rod arrangement for an engine like that shown in Fig.9 wherein the crankshaft cranks are arranged in a pattern opposite tothat shown in relative positions of the crankshaft crankpins and theconnecting rods for the Fig. 1 arrangement;

Fig. 4 is a diagrammatic end elevation of an engine arrangement similarto that shown in Figs, 1-3 wherein the crankshaft crankpins for the twocylinder banks spiral in opposite directions to the arrangement shown inFigs. 1 3;

Fig. 5 is a diagrammatic end elevation showing the crankshaft crankpinand connecting rod positions for the crankshaft arrangement shown inFig. 4;

Fig. 6 is a diagrammatic end elevation of another form of odd angle,balanced, V-eight engine embodying this invention;

Fig. 7 is a diagrammatic end elevation showing the crankshaft crankpinand the connecting rod arrangement for the engine shown in Fig. 6;

Fig. 8 is a diagrammatic end elevation of the crankshaft crankpin andthe connecting rod arrangement for an engine like that shownin Fig.

Fig. 10

Fig. 12 is a diagrammatic end elevation of another form of odd angle,balanced V-eight engine embodying this invention;

Fig. 13 is a diagrammatic end elevation showing the crankshaft crankpinand the connecting rod arrangement for the engine shown in Fig. 12; and

Fig. 14 is a diagrammatic end elevation showing the crankshaft crankpinand the connecting rod arrangement for an engine similar to that shownin Fig. 12 wherein the crankshaft crankpin arrangementis opposite tothat shown in Fig. 13.

It has often appeared that it would be quite advantageous to use V-eightengines of other than or 180 degree bank angles if such engines could becompletely balanced by crankshaft counterweighting alone and if evenring intervals and equal cylinder bore spacing would also becharacteristic of such engines. Set forth below is a description of agroup of engines meeting the above requirements.

As a result of the application of the formulae set forth hereafter andcertain other mathematical theory that is well known in the art, it hasbeen determined, for the first time -it is thought, what V-eightengines. having bank angles other than 90 or 180 degrees, provide enginearrangements that maybe completely balanced by crankshaftcounterweighting alone and wherein the ring intervals and the cylinderbore spacing are each-even. It has been further determined that the fourV-eight engines having bank angles (d) of 36.9, 53.1, 126.9 and 143.1degrees respectively are the only engine arrangements other than 90 and180 V-eight arrangements that meet the above requirements. It will beseen that each of these odd angle V-eight engines are in realitydifferent members of a single engine group and thus they representmerely different forms of the same invention. It hasbeen furtherdetermined that even if the cylinder bore spacing in any of the abovenoted engines is varied slight.- ly to permit the use of diierent sizecrankshaft bearings between the several cranks of any crankshaft, thatstill the above noted bank angles are substantially cor-rect within plusor minus 1 or 2 degrees. Furthermore, the exact bank angle to insurecomplete engine balance for any given cylinder bore spacing or anyvariation from even firing intervals can be determined from the formulaeset forth below.

The four V-eight engines herein describedhave the desirable features ofshort length, simplicity of design and perfect balance whichcharacterize the conventional QO-degree type` of V-eight engine. A primeadvantage of these four V-eight engines as compared to the conventional90 degree V-eight engines lies in their width and/or height reductionsover the 90 degree V-eight engines. A difculty experienced withconventional 90 degree V-eight engines, particularly the newer enginesusing overhead valves, is that their large width results in crowding ofengine and accessory .units in the engine compartment. The accessibilityof parts mounted on the engine, such as the carburetor and the oil lter,is adversely affected. Not only the engine units, but other accessoryunits, commonly mounted in the engine compartment of a motor vehicle,such as the steering mechanism, heater, battery and the like are alsocrowded because of the engine width.

The possibility of building a satisfactory narrow-angle V-8 engine hasbeen investigated by a number of others in the past but the best typeswhich have appeared to date have all had serious dynamic unbalancesinherent in their crank and cylinder arrangements. In addition some ofthe narrow angle V-eights proposed have had uneven firing intervals. Twoof the engines herein described, namely the 36.9 and 53.1 degree angleV-eight engines are the only known engines in that category which havecomplete inherent dynamic balance and even firing intervals as Well asequal cylinder bore spacing. The bank angles of 36.9 and 53.1 degreesare more exactly the arc tangent selon and arc tangent respectively. Theother two V-eight engines of this disclosure are V-eight engines of widebank angle having angles of 126.9 and 143.1 degrees. More exactly, theseangles are are tangent and arc tangent respectively. These engines havethe advantage of low height when compared with the conventional 90degree V-eight and will be suitable for installations where height isrestricted.

It can be proven mathematically from the formulae appearing hereafterthat the four V- eight engines disclosed along with the conventional 90degree V-eight and the conventional eight-cylinder opposed or 180 degreeV-eight engine are the only two-bank eight-cylinder engines possiblehaving (l) primary and secondary reciprocating inertia force balance,(2) primary and secondary inertia couple balance, and 3) even firingintervals. In the four disclosed odd angle V-eight engines and theconventional degree V-eight engine primary couple balance is achievedwith the aid of crankshaft counterweighting alone. Each of the four oddangle V- eig'nt engines herein disclosed employs eight crankpins. Thecrankshafts for the 53.1 and the 125.9 degree V-8 engines are the same,and the crankshafts for the 36.9 and the 143.1 degree V-8 engines arethe same. All the crankshafts are typified by opposite spiralling of.thetwo groups of four crankpins each for each of the two banks. As withmost crankshafts, each of the described crankshafts can be built withthe crankpins following each other at the same intervals in either theclockwise or counterclockwise direction. It is possible to change thebank angle cf any of the four odd angle V-eight engines slightly andstill maintain its balance by using an uneven bore spacing or unevenfiring intervals or both if such should be desired.

Fig. 1 shows a crankshaft 22 for a V-eight engine wherein the twosimilar banks R. and L of the engine are arranged with a bank angle (d)of 53.1 degrees therebetween as clearly shown in Figs. 2 and 3. Cranks2|, 23, 25 and 2l of the crankshaft 2B are connected to the pistons inthe cylinders of the left bank L while cranks 22, 24, 26 and 28 ofcrankshaft 28 are connected to the Distons in the cylinders of the rightbank R of the engine. The cylinder bores of each bank and consequentlythe cranks of the crankshaft diagrammatically disclosed in Fig. 1 areequally spaced longitudinally of the engine. From Fig. 3 it will benoted that crank 23 is spaced clockwise from crank 2l by 90 degrees andcrank 25 is spaced clockwise from crank 23 by 180 degrees with crank 2lspaced clockwise from crank 25 by 27o degrees. Accordingly, cranks 2|and 21 are diametrically opposed as are cranks 23 and 25. Furthermore,each of cranks 2l, 23, 25 and 21 is spaced either 90 degrees or somemultiple of 90 degrees from each of the other cranks of theassociated'engine cylinder bank L. Likewise, from Fig. 3, it will benoted that crankfZii is spaced counterclockwise from crank 22 by 90degrees, crank 28 is spaced counterclockwise from crank 24 by 180degrees and crank 28 is spaced counterclockwise from crank 2S by 27()degrees. It will be noted that cranks 22 and 28 are diametricallyopposed as are cranks 2e and 26 and that each of cranks 22, 2i, 2B and28 are spaced either 90 degrees or a multiple of 90 degrees from each ofthe other cranks of the associated engine cylinder bank R. It can thusbe said that the cranks of the two banks R and L of this engine spiralin opposite directions. Connecting rods 3 i-S are connected to thecranks 2i-28 in conventional manner and each connecting rod has a pistonconnected thereto in accordance with standard practice. From Figs. 1 and3 it is clear that the crankshaft for this balanced, odd-angle V-eightengine has eight cranks comprising two sets of four cranks each whereinthe cranks of each set spiral about the crankshaft axis in oppositedirections. This particular crank arrangement is one of the featuresthat distinguishes this invention from both the conventional 90 degreeand degree V-eights and from other odd angle V- eight engines that havebeen proposed in the past. In Fig. 3 the numeral 30 represents the planecontaining the primary couple and it will be noted that this plane isbetween the planes of cranks 2l and 22. The counterweights 4I46 areplaced So as to completely balance the primary couple. With thecounterweighting arrangement shown the several counterweights are alloffset angularly from the plane 30 that includes the primary couple ofthe engine but the arrangement still completely balances the engineprimary couple and also develops forces that act to reduce the bearingloads at the central crankshaft bearing 40. 'I'he counterweight patternshown may be varied to meet varying circumstances and need not beidentical to that disclosed.

As previously mentioned the cylinder bore spacing a for the enginesherein disclosed is even or constant and thus if.a represents thespacing between the adjacent intermediate cranks of either engine bank(see Fig. 1) then 0, which represents the spacing between the endcranksof either engine bank, is equal to 3 a. .This relationship C=3a is ofimportance in developing the formulae that pertains to the group ofengines involving this invention for it will be found that the angle 1'in each of these engines equals the arc tangent 18 45 d egrees whenC'=3a. The angle 1' is that angle that the front crank of a bank ofcylinders makes with the axis of the cylinders of that bank when therocking couple of that bank is a maximum.

Looking now at Figs. 2 and 3, it will be seen that the angle f is theangle by which the front crank 2l of left bank L leads the front crank22 of right bank R. This angle f will turn out to be actually 36.9degrees for the 53.1 degree bank angle V-eight when the appropriate,after described, equations are solved.

The angle B shown in Fig. 2 is the angle by which the primary rockingcouple in one bank L leads the primary rocking couple in the other bankR. The phase angle of the primary rocking couple for each of the banks Land R can be determined by application of either graphical ormathematical means known to the engine design art and which means arenot thought to require explanation for an understanding of thisinvention. It can further be established that the primary rocking couplein one bank L or R can lead or follow the front crank 2| or 22respectively in that engine bank by the angle "r. The symbol "h in thebelow equations represents a firing interval and for equal firingintervals with the crankshaft arrangement disclosed it will be foundthat h equals 90 degrees or a multiple thereof. Accordingly, any of thethree following relationships are possible for inherently balancedV-eight engines of two four cylinder banks:

(1) Bib for 90 and 180 degree V-eight engines.

(2) B=h+2r for certain odd angle, inherently balanced V-eight engines.

(3) Bzh-Zr for certain other odd angle, in-

herently balanced V-eight engines.l

It is now possible to write a set of equations for -eight engines whichwill completely denean engine having:

(a) a resultant primary rotating couple that can be completely balancedby crankshaft counterweighting;

(b) combinations of crankshaft crank groups that have reciprocatinginertia force balance;

- 53.1 degrees toone another.

(c) even spacing of the cylinder bores in each .bank of the engine; and(d) even ring intervals.

(I) B=180d where d=the bank angle. (n) B=h, rugzak-2r.

(III) r=arc tangent 1/3=18.45 degrees. (IV) h=0, 90, 180, 27() degrees.

By solving the above equations it will be found that V-eight engineshaving bank angles (d) of and 180 degrees as well as the four odd angleV-eights that have 36.9, 53.1, 126.9 and 143.1 bank angles (cl) are theonly V-eight engines meeting the aforementioned requirements of balance,equal bore spacing and even ring intervals.

By rearranging Equation I above it will be found that d:-B, or expressedverbally, the angle between' the banks (d) equals 180 degrees minus theangle (B) by which the primary rocking couple in one bank leads theprimary rocking couple in the other ba By combining Equations II and IIIabove and considering the aforementioned Equations 1, 2 and 3, it willbe found that B=h+36-9 degrees for certain inherently balanced odd angleV- eight engines and B:h*36.9 degrees for certain other inherentlybalanced odd angle V-eight engines. The conventional 90 or 180fdegreebank angle V-eight engines are omitted from this discussion for obviousreasons.

Now if hz, 90, 180 and 270 degrees then for B=hi36-9 degrees, it will befound that B=i36-9 degrees, $126.9 degrees, i531 degrees and i143.1degrees for the various aforementioned values of h.

It can be shown mathematically that whenever :180-d, the primaryreciprocating inertia couples of the angled banks of the several enginesherein Ydisclosed always combine to give a resultant rotating couplethat extends in a plane that bisects the angle between the front cranksof the two banks so that this couple can be completely balanced by acrankshaft counterweighting alone. When even firing intervals arerequired and even bore spacing is used balanced engines are obtainedwith bank angles d of 36.9, 53.1, 126.9 and 143.1 degrees. These are theonly angles that will give inherently balanced odd angle V-eightengines. Because of the basic crankshaft crank arrangement disclosed foreach engine of the group herein described, primary force balance andsecondary force and couple balance are alsov achieved in each of thefour odd angle V-eight engines herein described.

Figs. 4 and 5 show an odd angle V-eight engine wherein the two equallyspaced four cylinder engine banks are arranged at an angle (d) of Thisis the case' with the Figs. 1-3 arrangement but in the Figs. 4 and 5arrangement the cranks of the crankshaft are oppositely arranged tothose shown in Figs. 1-3. In Figs. 4 and 5 the reference numerals aresimilar to those shown in Figs. 1-3 but are primed to be distinguishablefrom the corresponding numerals in Figs. 1-3. It will be noted that inFigs. 4 and 5 the cranks 2|', 23', 25 and 21 spiral or twistcounterclockwise from front to rear and are connected to the right bankR whereas in Figs. 1-3 lthe opposite relationship existed. Similarly inFigs. a and the cranks 22', 24', 26 and 28 spiral or coil clockwisc fromfront to rear and are connected to the left bank L' of the engine. InFigs 1-3 just the opposite relationship existed. All other relationshipsrelative to crank angles L the plane of the resultant rotating coupleand the angle r are the same for Figs. 1-3 and Figs. 4 5. Connectingrods 3|'38 connect the cranks 2I-28' respectively to the pistons in thetwo banks of cylinders as shown in Fig. 5.

Figs. 6 and '1 show a second narrow angle V- eight embodying thisinvention wherein the two banks of cylinders R2 and L2 are arranged atan angle (d) to each other of 36.9 degrees. In .I

this narrow angle V-eight the crankshaft 5|) has eight angularly spacedapart cranks 5|-58 inelusive,l arranged in two sets of four cranks each.

One set is composed of cranks 5|, 53, 55 and 51 that spiralcounterclockwise from front to rear and are spaced 90 degrees apart clueto` cra-nk 53 being 90 degrees counterclockwise from crank 5|, crankbein'g 180 degrees counterclockwise from crank 53 and crank 51 being 270degrees counterclockwise from crank 55. The other set of cranks iscomposed of cranks .52, 54, 55 and 58 that spiral clockwise from irontto rear and are 90 degrees apart due to crank 54 being 9 0 vdegreesclockwise from crank 52, crank 5B being 180 degrees clockwise from crank54 and crank 58 being 270 degrees clockwise from crank 5B. Connectingrods 5|-6 connect the cranks 4'5l-5|?. to their respective pistons andcylinder bores. As is evident left bank L2 includes the cylindersconnected to cranks 5|, 53, 55 and 51 whereas right bank R2 includes thecylinders and pistons that are connected to cranks 52, 54, 56 and 58.The plane that bisects the angle between the cranks 5| and 52 containsthe resultant of the primary reciprocating inertia forces of the twoangularly related banks of cylinders R2 and L2.

Fig. 8 shows an end elevation similar to Fig. '7 but representing anvarrangement wherein the two sets of cranksi'al, 53', 55', 51' and 52',54', 55', 58' respectively are oppositely arranged to theircorresponding elernents shown in Figs. 6 and 1. Cranks 51253', 55' andk51' spiral clockwise from iront to rear and are spaced equally atmultiples of 9G degrees. Likewise cranks 52', 54', 56' and 5S' spiralcounterclockwise from front to rear and are spaced equally at intervalsof 90 degrees or multiples thereof. The plane 59' .includes theresultant rotating couple of the primary reciprocating inertia couples.All relationshipsthat applied to the Fig. 5 and 7 form arelikewise trueof the Fig. 8 form of the invention. Connecting rods 6|'68' connect thecranks 5|5,8' respectively to the pistons in the two .banks of cylindersas shown in Fig. 8.

Figs. 9 and 10 show one form of wideangle V- eight engine that embodiesthis invention.v V'The two banks R3 and L3 of this engine are arrangedAat an angle (d) of 126.9 degrees to each other. In this wide angleAV-eight engine the crankshaft 1e has eight angularly spaced apartcranks 'ii-18 inclusive arranged in twosets of four cranks each with thecranks of each set spiralling in opposite directions about thecrankshaft axis. 'One ySetv of .cranks is composed .of cranks 1|., '13,15 and A17| that vspira-l oounterclockwise Afrom front torear .about thecrankshaft axis and are equally spaced vat 90 degree interi/'als fromone another due to Ycrank 13-being :90 degrees counterclockwise fromcrank 1i|,cr.ank .15 being 180 'degrees counterclockwise fromfcrank 13and crank 11 being 270 degrees counterclockwise from crank 15. Cranks1|, 13, 15 and 11 are connected by connecting rods 8|, 83, 85 and 81respectively to the pistons in the left bank of cylinders L3. The otherset of cranks 12, 14, 16 and 13 spiral clockwise from front to rearabout the crankshaft axis and are equally spaced at 90 degrees clockwisedue to crank 14 being 90 degrees clockwise from crank 12, crank 16 being180 degrees clockwise from crank 14 and crank 18 being 270 degreesclockwise from crank 15. Cranks 12, 14, 16 and 18 are connected byconnecting rods 82, 84, 86 and 88 respectively to the pistons in theright bank of cylinders R3. The plane that bisects the angle between thecranks 8| and 8.2 contains the resultant rotating couple of the primaryreciprocating inertia forces of the two banks of cylinders. The severalangular relationships that exist for the other forms of this inventionare likewise true of this form of the invention.

Fig. 1l shows an end elevation of engine similar to that shown in Figs.9 and 10 but disclosing an arrangement wherein the two sets ofcrankshaft cranks 1|', 15', 15', 11' and 12", 14', 16' and 1Brespectively spiral in opposite directions to that shown in Figs. 9 and10. Cranks 1 |313', 15' and 11' spiral clockwise from front to rear andare arranged at equally spaced angular intervals that are inuitiplcs of90 degrees. Cranks 1|', 13', 15' and '11" are connected to the pistonsin the right bank ci ,cylinders R3 by connecting rods 8|', 83', 85 and81' respectively. Cranks 12', 14', 15' and 18' spiral counterclockwisefrom front to rear and are arranged at equally spaced angular intervalsthat are multiples oi 90 degrees. Cranks 12', 14', 15', 18 are connectedby connecting rods 82', 84', 8,5 and 82 to the pistons in the left bankL3. The plane til' that bisects the angle between cranks 1|' and 12'contains the resultant rotating couple of the primary reciprocatinginertia force rocking couples.

Figs. 12 and 13 show another form of wide angle V-eight engine thatembodies this invention. The two banks R4 and L4 of this engine arearranged at an angle (d) or" 143.1 degrees to each other. vIn this wideangle V-eight engine the crankshaft 99 has eight angularly spaced apartcranks `SI--Qii inclusive arranged in two sets of four .cranks each withthecranksof eachset spiralling in opposite .directions about thecrankshaft axis. One set of cranks is composed of cranks 9|, 93, and 51that spiral clockwise from front to rear about the crankshaft .axis andare equally spa-ced .at 90 degrees intervals from one another due tocrank 93 ,being 90 degrees clockwise from crank 9|, crank 95 being 180degrees clockwise from crank 53 and crank ,9 1 being 270 degreesclockwise `from crank 95. Cranks 9|, 93, 95 and S1 are ccnnectedfbyconnecting rods 19|, |93, |05 and 01 to the pistons in the left bank ofcylinders L?. The other set of cranks 92, 94, 96 and 98 spiralcounterclock-wise from front to rear about the crankshaft axis and areequally spaced at 90 degree intervals clue to crank 94 being 90 degreescounterclock-wise from crank 92, crank 9S being 180 .degreescounterclockwise from crank 94 and crank VSii-being .27.0 degreescounterclockwise from crank 9S. Cranks 92, 94, 96 and gareconnected tothe pistons in the right bank of cylinders R4 by connecting rods |92,|114, U16-and |08 respectively. The plane 100 that `bisects theVangIebetween cranks 9| and 92 contains the .resultant rotating coupleof the primary reciprocating inert-aorce rocking couples 4of the :twoengine banks R4, L4. The several angular relationships that exist forthe other forms of the invention are likewise true of this form of theinvention.

Fig. 14 shows an end elevation of an engine similar to that shown inFigs. 12 and 13 but disclosing an arrangement wherein the two sets ofcrankshaft cranks 9|', 93', 95', 91 and 92', 94', 96' and 98'respectively spiral in opposite directions to that shown in Figs. 12 and13. Cranks 9|', 93', 95' and 91 spiral counterclockwise from front torear and gular intervals that are multiples of 90 degrees. Cranks 9|',93', 95 and 91' are connected to the pistons of the right bank R4' byconnecting rods l, |93', |35' and |01 respectively. Cranks 92', 94', 96'and 98' spiral clockwise from front to rear about the crankshaft axisfrom front to rear and are arranged at equally spaced angular intervalsthat are multiples of 90 degrees. Cranks 92', 94', 96' and 98' areconnected by connecting rods |02', |64', |96' and |08 to the pistons ofthe left bank L4'. The plane |00' that bisects the angle between cranks9| and 92' contains the resultant rotating couple of the primaryreciprocating inertia force rocking couples of the two engine banks. Theother angular relationships that apply to the other forms of thisinvention likewise apply to the form shown in Fig. 14.

I claim:

1. In an inherently balanced eight cylinder V- type engine having a bankangle of other than ninety-degrees or full multiples thereof comprisingtwo banks of four cylinders each wherein the angle between the two banksequals 180 degrees minus the angle by which the primary rocking couplein one bank leads the primary rocking couple in the other bank andwherein the crankshaft for the engine includes eight angularly spacedcranks arranged in two sets of four equally angularly spaced apartcranks arranged such that the directions of spiral of the two sets ofcranks are opposite when looking from the front crank of each settowards the rear crank thereof and the cranks in each bank are arrangedsuch that the second crank is radially spaced from the first crank byninetydegrees, the third crank radially spaced from the second crank byone-hundred-eighty degrees, and the fourth crank radially spaced fromthe third crank by two-hundred-seventy degrees.

2. In an inherently balanced eight cylinder V- type engine comprisingtwo banks of four cylinders each wherein the angle between the two banksequals substantially 36.9 degrees and wherein the crankshaft for theengine includes arranged in two eight angularly spaced cranks sets offour equally angularly spaced apart cranks arranged such that thedirections of spiral of the two sets of cranks are opposite when lookingfrom the front crank of each set towards the rear crank thereof and thecranks in each bank are arranged such that the second crank is radiallyspaced from the rst crank by ninetydegrees, the third crank radiallyspaced from the second crank by one-hundred-eighty degrees, and thefourth crank radially spaced from the third crank by two-hundred-seventydegrees.` 3. In an inherently balanced eight cylinder AV- type enginecomprising two banks of four cylinders each wherein the angle betweenthe two banks equals substantially 53.1 vdegrees and wherein theVcrankshaft forthe engine includes eight angularly spaced cranks arrangedintwo sets of four equally angularly spaced apart cranks arranged suchthat the directions of spiral are arranged at equally spaced ant 10 ofthe two sets of cranks are opposite when looking from the front crank ofeach set towards the rear crank thereof and the cranks in each bank arearranged such that the second crank is radially spaced from the firstcrank by ninetydegrees, the third crank radially spaced from the secondcrank by one-hundred-eighty degrees, and the fourth crank radiallyspaced from the third crank by two-hundred-seventy degrees.

4V. In an inherently balanced eight cylinder V- ytype engine comprisingtwo banks of four cylinders each wherein'the angle between the two banksequals substantially 126.9 degrees and wherein the crankshaft for theengine includes eight angularly spaced cranks arranged in two sets offour equally angularly spaced apart cranks arranged such that thedirections of spiral of the two sets of cranks are opposite when lookingfrom the front crank of each set towards the Arear crank thereof and thecranks in each bank are arranged such that the second crank is radiallyspaced from the first crank by ninetydegrees, the third crank radiallyspaced from the second crank by one-hundred-eighty degrees, and thefourth crank radially spaced from the third crank by two-hundred-seventydegrees.

5. In an inherently balanced eight cylinder V- type engine comprisingtwo banks of four cylinders each wherein the angle between the two banksequals substantially 143.1 degrees and wherein the crankshaft for theengine includes eight angularly spaced cranks arranged in two V'sets offour equally angularly spaced apart .cranks arranged such that thedirections of spiral of the two sets of cranks are opposite when lookingfrom the front crank of each set towards the rear crank thereof and thecranks in each bank are arranged such that the second crank is radiallyspaced from the first crank by ninety-l degrees, the third crankradially spaced from the second crank by one-hundred-eighty degrees, andthe fourth crank radially spaced from the third crank bytwo-hundred-seventy,degrees.

` 6. In an inherently balanced eight cylinder V- type engine having abank angle of other than ninety-degrees or full multiples thereofcomprising two banks of four equally spaced apart cylinders alternatelyarranged longitudinally of the engine wherein the angle between the twobanks. equals degrees minus the angle by which the primary rockingcouple of one bank leads the primary rocking couple of the other bankand wherein the crankshaft for the engine ,includes eight angularlyspaced cranksA arranged in two sets of four equally angularly spacedapart cranks each with the cranks of each set arranged such that thedirection of coil of each set of cranks when traveling from the frontcrank of each set to the rear crank thereof is opposite to that of theother set and wherein the front crank of one set is angularly spacedfrom the front. crank of the other set by 36.9 degrees and the cranks ineach bank are arranged such that the second crank is radially spacedfrom the first crank byv gine includes eight angularly spaced cranksarranged in two sets of four equally angularly spaced apart cranks eachwith the cranks of each set arranged such that the direction of coil ofeach set of cranksv when traveling fromv the front crank of each set tothe rear crank thereof is opposite to that of the other set and whereinthe front crank oi one set is angularly spaced from the front crank ofthe other set by substantially 143.1 degrees and the cranks in each bankare arranged such that the. second crank is radially spacedfrom the rstcrank by ninetydegrees, the third crank radially spaced from the secondcrank by one-hundred.-eighty degrees, and the fourth crank radiallyspaced from the third crank by two-hundred-seventy degrees.

8. In an eight cylinder V-typeengine comprising two banks of fourequally spaced apart cylinders alternately arranged longitudinally ofthe engine wherein the angle between the two banks equals substantially53.1 degrees and wherein the crankshaft. for the engine includes eightangularly spaced cranks arranged in two setsof four equally angularlyspaced apartv cranks each with the cranks of each set arranged such thatthe direction of coil of each set of cranks when traveling from thefront crank of each set to the rear crank thereof is opposite tov thatof the other set and wherein the iront crank of one set is. angularlyspaced from the front crank of the other set by substantialy 36.9degrees.

9. In an eight cylinder V-type engine comprising two banks of fourequally spaced, apart. cylinders alternately arranged longitudinally ofthe engine wherein. thev angle between the two. banks equals.substantially 1261.9 degrees and wherein the crankshaft for the engineyincludes eight angularly spaced cranks arranged in two sets of fourequally angularly spaced apart cranks each with the cranks of each setarranged such that the. direction of coil of each set of cranks whentraveling from the iront crank of each set to the rear crank thereof isopposite to that of the other set and wherein the fronty crank. of. oneset is angularly spaced from the front crank of the. other set bysubstantially 36.9 degrees. Y

10. In aninherently balanced eight` cylinder V- type engine comprisingtwo banks. of four equally spaced apart cylinders alternately arrangedlongitudinally of the. engine wherein the angle between the two banksequals substantially 143.1 degrees. and wherein the crankshaft for theengine includes eight angularly spaced cranks arranged in two sets offour equally angularly spaced apart cranks each with the cranks of eachset arranged such that the direction of coil of each set of cranks whentraveling from the front crank of each set tothe rear crank thereof isopposite to that of the other setand wherein the front crank of one setis angularly spaced from the front crank of the other set bysubstantially 143.1 degrees and the cranks in each bank are arrangedsuch that the second crank is radiaily spacedfrom the. first crank byninetydegrees, the third crank radially spaced from the second crank byone-hundred-eighty degrees, and the fourth. crank radially spaced fromthe third crank by two-hundred-seventy degrees.

11. An inherently balanced eight cylinder V- type engine having a bankangle of other than ninety-degrees or full multiples thereof` comprisinga crankshaft extending longitudinally of the engine and a pair of banksof four cylinders each, said cylinder banks being arranged at an angleto one another such that the resultant gularly of the of the primaryreciprocating inertia force rocking couples of the twobanks is arotating couple that lies in a plane extending perpendicular to and.longitudinally of the crankshaft whereby said resultant rotating couplecan be counterbalanced` by crankshaft counterweighting alone, saidcrankshaft having eight angularly spaced apart cranks comprising twosets of four cranks each wherein the cranks of each set are equallyspaced angularly oi the crankshaft at ninety degree intervals and thedirection of twist of the cranks of one set going from the front crankto the rear crank thereof is opposite to the direction of twistof theother set and the cranks in each bank are arranged such that the secondcrank is radially spaced. from the rst crank by ninetydegrees, the thirdcrank radially spaced from the second crank by one-hundred-eightydegrees, and the fourth crank radially spaced from the third crank bytwo-hundred-seyenty degrees.

12- An inherently balanced eight cylinder V- type engine comprising acrankshaft extending longitudinally of the engine and a pair of banks offour cylinders each, said cylinder banks being arranged at an angle toone another of 36.9 degrees such thatY the resultant of the primaryreciprocating inertia force rocking couples of the two banks is arotating couple that lies in a plane extending perpendicular to andlongitudinally of the crank shaft whereby said resultant rotatingcouplecan be counterbalanced by crankshaft counterweighting alone, saidcrankshaft having eight angularly spaced apart cranks comprising twosets of four cranks each wherein the cranks of each setV are equallyspaced angularly of the crankshaft at ninety degree intervals and thedirection oi twist of the cranks of one set going from the iront crankto the rear crank thereof is opposite to the direction of twist of theother set.

13. An inherently balanced eight cylinder V- type engine comprising acrankshaft extending longitudinally of the engine and a pair of banks offour cylinders each.1 said cylinder banks being arranged at an angletoone another of 53.1 degrees such that the resultant of the primary.

reciprocating inertia force rocking couples of the two banks is arotating couple that lies in a plane extending perpendicular to andlongitudinally of the crankshaft whereby said resultant rotating couplecan be counterbalanced by crankshaft counterweighting alone, saidcrankshaft having eight angularly spaced apart cranks comprising twosets of four cranks each wherein the cranks of each set are equallyspaced ancrankshaft at ninety degree intervals andthe direction of twistof the cranks of one set going from the front crank to the rear crankthereof is opposite to the direction of twist of the other set.

14. An inherently balanced eight cylinder V- type engine comprising acrankshaft extending longitudinally of the engine and a pair of banks offour cylinders each, said cylinder banks being arranged at an angle toone another of 126.9 degrees such that the resultant of the primaryreciprocating. inertia forceV rocking couples of the two banks is arotating couple that lies in a plane extending perpendicular to andlongitudinally of the crankshaft whereby said resultant rotating couplecan be counterbalanced by crankshaft counterweighting alone, saidcrankshaft having eight angularly spaced apart cranks comprising twosets of four cranks each wherein the cranks Qi each set are equallyspaced y 13L anguIarly of the crankshaft at ninety degree intervals andthe direction of twist of the cranks of one set going from the frontcrank to the rear crank thereof is opposite to the direction of twist ofthe other set.

15. An inherently balanced eight cylinder V- type engine comprising acrankshaft extending longitudinally of the engine and a pair of banks offour cylinders each, said cylinder banks being arranged at an angle toone` another of 143.1 degrees such that the resultant of the primaryreciprocating inertia force rocking couples of the two banks is arotating couple that lies in a plane extending perpendicular to andlongitudinally of the crankshaft whereby said resultant rotating couplecan be counterbalanced by crankshaft counterweighting alone, saidcrankshaft having eight angularly spaced apart cranks comprising twosets of four cranks each wherein the cranks of each set are equallyspaced angularly ofthe crankshaft at ninety degree intervals and thedirection of twist of the cranks of one set going from the front crankto the rear crank thereof is opposite to the direction of twist of theother set.

16. An inherently balanced eight cylinder V- type engine having a bankangle of other than ninety-degrees or full multiples thereof comprisinga crankshaft extending longitudinally of the engine and a pair of banksof four equally spaced cylinders each, said cylinder banks beingarranged at an angle to one another such that the resultant of theprimary reciprocating inertia force rocking couples of the two banks isa rotating couple that lies in a plane extending perpendicular to andlongitudinally of the crankshaft whereby said resultant rotating couplecan` be counterbalanced by crankshaft counterweighting4 alone, saidcrankshaft having eight angularly spaced apart cranks comprising twosets of four cranks each wherein the cranks of each set are equallyspaced angularly of the crankshaft at ninety degree intervals and thedirection of twist of the cranks of one set going from the front crankto the rear crank thereof is opposite to the direction of twist of theother set and the cranks in each bank are arranged such that the secondcrank is radially spaced from the first crank by ninety-degrees, thethird crank radially spaced from the second crank by one-hundredeightydegrees, and the fourth crank radially spaced from the third crank bytwo-hundredseventy degrees.

17. An inherently balanced eight cylinder V-eight engine comprising twobanks of four cylinders each arranged at an angle of substantially 36.9degrees and including a crankshaft having eight angularly spaced cranksarranged in two sets of four oppositely twisting patterns with eachcrank connected to an engine cylinder in an arrangement whereby theresultant of the primary reciprocating inertia force rocking couples ofthe two cylinder banks is a rotating couple that can be` balanced bycrankshaft ccunterweighting alone and wherein the secondaryreciprocating inertia force rocking couples and the primary andsecondary reciprocating inertia forces are inherently balanced withineach bank.

1S. An inherently balanced eight cylinder V-eight engine comprising twobanks of four cylinders each arranged at an angle of substantially 53.1degrees and including a crankshaft having eight angularly spaced cranksarranged in two sets of four oppositely twisting patterns with eachcrank connected to an engine cylinder in an arrangement whereby theresultant of the primary reciprocating inertia force rocking couples ofthe two cylinder banks is a rotating couple that can be balanced bycrankshaft counter- Weighting alone and wherein the secondaryreciprocating inertia rocking couples and the primary 'and secondaryreciprocating inertia forces are inherently balanced within each bank.

19. An inherently balanced eight cylinder V-eight engine comprising twobanks of four cylinders each arranged at an angle of substantially 126.9degrees and including a crankshaft having eight angularly spaced cranksarranged in two sets of four oppositely twisting patterns with eachcrankconnected to an engine cylinder in an arrangement whereby the resultantof the primary reciprocating inertia force rocking couples of the twocylinder banks is a. rotating couple that can be baalnced by crankshaftcounterweighting alone and wherein the secondary reciprocating inertiaforce rocking couples and the primary and secondary reciprocatinginertia forces are inherently balanced within each bank.

20. An inherently balanced eight cylinder V-eight engine comprising twobanks of four cylinders each arranged at an angle of substantially 143.1degrees and including a crankshaft having eight angularly spaced cranksarranged in two sets of four oppositely twisting patterns with eachcrank connected to an engine cylinder in an arrangement whereby theresultant of the primary reciprocating inertia force rocking couples ofthe two cylinder banks is a rotating couple that can be balancedbycrankshaft counterweighting alone and wherein the secondaryreciprocating inertia force rocking couples and the primary andsecondary reciprocating inertia forces are inherently balanced withineach bank.

21. An eight cylinder V-type engine comprising a crankshaft extendinglongitudinally of the engine and a pair of banks of four cylinders each,said cylinder banks being arranged at an angle to one another of 36.9degreesV such that the resultant of the primary reciprocating inertiaforce rocking couples of the two banks is a rotating couple that lies ina plane extending perpendicular to and longitudinally of the crankshaftwhereby said resultant rotating couple can be counterbalanced bycrankshaft counterweighting alone, said crankshaft having eightkangularly spaced apart cranks comprising twoI sets of four cranks eachwherein the cranks of each set are equally spaced angularly about thecrankshaft axis and the direction of twist of the cranks 0f one setgoing from the front crank to the rear crank thereof is opposite to thedirection of twist of the other set, said cranks of each set beingarranged such that going from front to rear of the crankshaft the secondcrank of each set is spaced angularly 9() degrees from the front crank,the third crank of each set is spaced angularly 180 degrees from thesecond crank and the fourth crank of each set isspaced angularly 270degrees g: from the third crank.

- the resultant of the primary reciprocating inertia force rockingcouples of the two banks is a rotating couple that lies in a planeextending perpendicular to and longitudinally of the crankshaft wherebysaid resultant rotating couple can be counterbalanced by crankshaftcounterweighting alone, said crankshaft having eight angularly spacedapart cranks comprising two sets of four cranks each wherein the cranksof each set are equally spaced angularly about the crankshaft axis `andthe direction of twist of the cranks of one setgoing from the frontcrank to the rear crank thereof is opposite to the direction of twist ofthe other set, said cranks of each set being arranged such that goingfrom front to rear of the crankshaft the second crank of each set isspaced angularly 90 degrees from the front crank, the third crank ofeach set is spaced angularly 180 degrees from the second crank and thefourth crank of each set is spaced angularly 270 degrees from the thirdcrank.

23. An eight cylinder V-type engine comprising a crankshaft extendinglongitudinally of the engine and a pair of banks of four cylinders each,said cylinder banks being arranged at an angle to one another of 126.9degrees such that the resultant of the primary reciprocating inertiaforce rocking couples of the two banks is a rotating couple that lies ina plane extending perpendicular to and longitudinally of the crankshaftwhereby said resultant rotating couple can be counterbalanced bycrankshaft counterweighting alone, said crankshaft having eightangularly spaced apart cranks comprising two sets of four cranks eachwherein the cranks of each set are equally spaced angularly about thecrankshaft axis and the direction of twist of the cranks of one setgoing from the front crank to the rear crank thereof is opposite to thedirection of twist of the other set, said cranks of each set beingarranged such that going from front to rear of the crankshaft the secondcrank of each set is spaced angularly 90 degrees from the front crank,the third crank of each set is spaced angularly 180 degrees from thesecond crank and the fourth crank of each set is spaced angularly 270degrees from the third crank.

24. An eight cylinder V-type engine comprising a crankshaft extendinglongitudinally of the engine and a pair of banks of four cylinders each,said cylinder banks being arranged at an angle to one another of 143.1degrees such that the resultant of the primary reciprocating inertiaforce rocking couples of the two banks is a rotating couple that lies ina plane extending perpendicular to and longitudinally of the crankshaftwhereby said resultant rotating couple can be counterbalanced bycrankshaft counterweighting alone, said crankshaft having eightangularly spaced apart cranks comprising two sets of four cranks eachwherein the cranks of each set are equally spaced angularly about thecrankshaft axis and the direction of twist of the cranks of one setgoing from the front crank to the rear crank thereof is opposite to thedirection of twist of the other set, said cranks of each set beingarranged such that going from front to rear of the crankshaft the secondcrank of each set is spaced angularly 90 degrees from the front crank,

. Number Name Date 1,665,521 Wrentmore Apr. l0, 1928 1,911,874 BarkeijMay 30, 1933 2,434,038 Ford Jan. 6, 1948 FOREIGN PATENTS Number CountryDate 102,378 Great Britain Mar. l5, 1917 274,564 Italy May 26, 1930 lthe third crank of eachssi-a` is' Sha degrees from the second crank acr'tgrarli crank of each set is spaced angularly 270 decgi; from the thirdcrank.

25. In an inherently balanced eight cylinder V-type engine having a bankangle of other than ninety-degrees or full multiples thereof comprisingtwo banks of four equally spaced apart cylinders alternately arrangedlongitudinally of the engine wherein the angle between `the two 'banksequals 180 degrees minus the angle by 'y which the primary rockingcouple of one bank leads the primary rocking couple of the other bankand wherein the crankshaft for the engine includes eight angularlyspaced apart cranks arranged in two sets of four equally angularlyspaced apart cranks each with the cranks of each set arranged such thatthe direction of coil of each set of cranks when traveling from thefront crank of each set to the rear crank thereof is opposite to that ofthe other set and wherein the front crank of one set is angularly spacedfrom 'the front crank of the other set by 143.1 degrees and the cranksin each bank are arranged such that the second crank is radially spacedfrom the first crank by ninety-degrees, the third crank radially spacedfrom the second crank by onehundred-eighty degrees, and the fourth crankradially spaced from the third crank by twohundred-seventy degrees.

26. In an inherently balanced eight cylinder V-type engine comprisingtwo banks of four equally spaced apart cylinders alternately arrangedlongitudinally of the engine wherein the angle between the two banksequals substantially 36.9 degrees and wherein the crankshaft for theengine includes eight angularly spaced cranks arranged in two sets offour equally angularly spaced apart cranks each withV the cranks of eachset arranged such that the direction of coil of each set of cranks whentraveling from the front crank of each set to the rear crank thereof isopposite to that of the other set and wherein the front crank of one setis angularly spaced from the front crank of the other set bysubstantially 143.1 degrees and the cranks in each bank are arrangedsuch that the second crank is radially spaced from the first crank byninety-degrees, the third crank radially spaced from the second crank byone-hundred-eighty degrees, and the fourth crank radially spaced fromthe third crank by two-hundred-seventy degrees.

References Cited in the le of this patent UNITED STATES PATENTS

